The present invention relates to a new and improved construction of a gas removal apparatus for an automatic firing weapon controlled by gas pressure.
In its more specific aspects, the present invention relates to a new and improved construction of a gas removal apparatus for an automatic firing weapon controlled by gas pressure. The automatic firing weapon possesses a weapon barrel containing a gas removal location, and a breechblock sleeve or housing in which the weapon barrel is replaceably or detachably fixed or secured. A gas cylinder is provided in the breechblock sleeve or housing and in this gas cylinder there is arranged a piston which is shiftable or displaceable by the gas pressure. A gas receiving opening or channel is provided in the breechblock sleeve or housing and leads to the gas cylinder. The gas removal location is located at a distance or spacing before or upstream of the gas receiving opening or channel viewed in the direction of the lengthwise axis of the weapon barrel. An outwardly-open groove or groove means provided in the outer surface of the weapon barrel extends in the lengthwise or longitudinal direction of the weapon barrel between the gas removal location and the gas receiving opening or channel, and a gas rail is arranged in the outwardly-open groove or groove means. This gas rail is held at its ends in the outwardly-open groove or groove means and contains a gas removal channel portion or section in its interior which connects the gas receiving opening of the breechblock sleeve or housing with the gas removal location of the weapon barrel.
Gas removal apparatuses of this type are known from prior art constructions. For example, in German Pat. No. 1,453,934, published Jan. 15, 1970, the gas removal channel structure consists of three sections, of which the first section in the weapon barrel is arranged transversely to the weapon barrel axis, the second section in the gas rail is arranged parallel to the weapon barrel axis, and the third section in the breechblock sleeve or housing is again arranged transverse to the weapon barrel axis. Therefore, the gas flow is deflected twice, in each case through a right angle. It has now been found that with high gas pressures and corrosive gases, the erosion in the gas channel is great.
Additionally, there is known to the art a gas-jet nozzle pipe for a breechblock drive and for the munitions transport of an automatic firing weapon, for example from European Pat. No. 0,158,705, published Oct. 23, 1985. This gas-jet nozzle pipe is located within a cylindrical bore of a barrel ring positioned parallel to the weapon barrel axis and which contains an axial inner bore extending parallel to the weapon barrel. This axial inner bore is connected to a gas removal bore formed from the outside obliquely in the weapon barrel and extending into the interior of the weapon barrel. This known gas-jet pipe nozzle contains in the region of its cylindrical jacket a connecting conduit extending obliquely from the gas removal bore to the axial inner bore. The connecting conduit exhibits a larger diameter from the entrance or inlet opening to the intersecting surface formed by the axial inner bore than the diameter of the axial inner bore, whereby the intersecting surface also constitutes the location of deflection of the throughflowing gas jet flowing within the gas-jet nozzle pipe and the gas jet is deflectable by an angle of inclination .alpha.&lt;90.degree. corresponding to the inclination of the connecting conduit with respect to the axial inner bore.
This known apparatus does have the advantage that the erosion essentially takes place inside the gas-jet nozzle pipe, i.e. in an easily replaceable part. This gas erosion is, however, extraordinarily great, so that the nozzle pipe must be constantly replaced.